Hi, Jon and thanks for your question.
You can retrieve your KTN by visiting the site below and filling in all the information or by calling the phone number for the Universal Enrollment Service:
Universal Enrollment Service: 855- 347- 8371 (Hours: Mon. - Fri. 8AM to 10PM, Eastern time).
Or you can visit this website and fill in all requested information: (I suggest trying the website first, as it's typically difficult to get through on the phone)
I hope this helped and wish you a wonderful trip!
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